Determination of Dry Rubber content(DRC) of field latex

ABOUT DRC :
DRC is the quantity in gm of rubber present in 100gm latex.

AIM OF THIS EXPERIMENT :
To determine the DRC of field latex.

APPARATUS :

• Cotton waste
• 50ml erlenmeyer flask
• Rubber stopper
• Electronic balance
• 250ml beaker
• Air oven
• Glass rod
• Wash bottle
  

REQUIREMENTS:

• Field latex
• Distilled water
• 2% Acetic acid

PROCEDURE:

• Shake well the given sample of latex bottle.
• Transfer 20-25ml of latex into a 50ml erlenmeyer flask provided with a stopper.
  

• Weigh about 10-20gm latex using an electronic balance into a 250ml beaker.
• Note the weight.
• Add equal amount of distilled water using a wash bottle & measuring cylinder.
  

  

• Keep the above contents undisturbed for a while.
• Add about 2-3ml of 2% acetic acid per gm of latex with gentle stirring.
  

• Keep the solution undisturbed for 15minutes in a water bath.
• When the serum is clear, filter the serum through whatman No:1 filter paper.
• Thickness of the coagulum is reduced to about 2mm by handroller.
• Collect any small particles of coagulum in the beaker by rubbing with main bulk.
• Wash the coagulum with running water for atleast 6 changes of water.
• Dry the coagulum at a temperature of 70 degree celsius for 1 day or for 50 degree celsius for 2 days.
• Cool & take the weight of the coagulum.
• Determination must be duplicated